With environmental awareness on the rise, electric vehicles are all the rage right now from the perspective of the transportation industry and automobile manufacturing industry. For instance, Volvo announced that it would no longer manufacture diesel engines and diesel engine-driven vehicles after 2020. Likewise, the British parliament passed a law to halt production of diesel and petrol vehicles by 2040 and increase uptake of electric vehicles. Hence, it is a common trend worldwide to replace gas-powered vehicles with electric vehicles gradually. The Taiwanese government encourages replacement of diesel engine-driven buses by Taiwan-made electric buses, though its ongoing achievements unveil drawbacks of conventional electric vehicles, namely the time-consuming, laborious, equipment-intensive changing of battery modules of conventional electric buses, compared with the refueling of diesel engine-driven buses. For this reason, bus companies in Taiwan nowadays are reluctant to switch to electric buses.
Conventional power packs for powering electronic products usually include a battery cell enclosed in a casing which provides physical protection, if any, to the battery cell. Power supplied by conventional power packs depends on how much electrical energy is stored in the battery cell, leading to short power supply duration of conventional power packs. Voltages of electronic products are seldom higher than 24V; hence, applications of conventional power packs are restricted to 3C products as well as charging and discharging emergency light-current systems for use with automotive alternators. Voltages higher than 48V are common only among power packs of a few green mobile power storage systems and electric buses, and the power packs are usually mounted on stationary storage racks or distributed uniformly in the vehicle, not only providing limited protection to battery modules or power packs, but also posing a risk of electric shock by generating an instantaneous or transient high voltage of 600-700V as soon as the electric buses start to be electrically driven. Furthermore, if the battery modules lack a quick-removal maintenance mechanism but get damaged, the power packs must be entirely removed in order to carry out maintenance, which is time-consuming and laborious. Moreover, the power packs have a high chance of failure when not waterproof and dustproof.
Most issued invention and utility model patents which claim a power pack are directed to a rechargeable lithium battery power pack or a mobile rechargeable lithium iron battery power pack for use with 3C products, such as computers, in a manner that the rechargeable lithium battery power pack or the mobile rechargeable lithium iron power pack is mounted on a stationary battery rack when it comes to mobile power storage systems or electric buses. The main drawback of the aforesaid stationary design is that it is time-consuming and laborious to change a power pack which has run out of power or failed. By contrast, bus companies always want their buses to undergo maintenance as rare as possible and as quickly as possible. In addition, the stationary storage racks disadvantageously have a low IP rating in terms of dustproof and waterproof protection for the power packs. On the other hand, whatever measures taken to render the stationary storage racks entirely dustproof and waterproof would be pricey, not to mention that every instance of mounting and demounting a power pack would inevitably reduce the dustproofing and waterproofing capability of the stationary storage racks to the detriment of long-term maintenance cost control.
Power packs mounted on conventional electric vehicles are fixed thereto to prevent the displacement and sliding of the power packs in x-direction and y-direction. However, power packs mounted on conventional electric vehicles running on bumpy roads are likely to jerk or vibrate in z-direction and thus get damaged. Conventional measures taken in attempt to prevent the z-direction damage involve fixing a power pack in place by fastening a bolted cover to the power pack from above or by fixing the power pack to the stationary storage rack with bolts and screws. However, the aforesaid conventional measures require mounting and demounting a lot of bolts and a cover, thereby rendering the operation process lengthy and adding to the weight of the power packs and stationary storage racks.